Piston ring



Oct. 31, 1933. 5, HN N 1,932,737

PISTON RING Filed May 51. 1932 NIH. IMHIIIIIHIH i -IIIHHHIIHIHII \nuenTov Chimes? dohnaon -M' W AWome Patented Oct. 31, 1933 UNITED STATESPATENT I OFFICE ADllicatio: if: )No. $4,488

This invention relates to piston rings and is outer to the innercurved sides of the ring, using concerned with a novel construction of oil draina circular saw, and are spaced'from each other ing ring for use particularly in internal combusat their end leaving intermediate sections 3 of tion engines wherein the speed of rotation of the the ring between the adjacent ends of the'slots 2.

5 engine crank shaft is-high with consequent rapid At the upper and lower outer corner portions 63 reciprocatory movements of the pistons. The of the ring and around the same, grooves'4 are ring of the present invention is designed to be cut, preferably rectangular in shape. These of a simple, easily manufactured economical grooves are located consecutively around the construction and one in which there is greater rlngand are separated at adjacent ends by inuniformity in the ring as to tension and wheretegral abutments 5. That is, the grooves 4 are 65 in the bearing surface of the ring against the not continuous but at periodic intervals around walls of the cylinder is ample, but not so wide the ring are separated from each other by interas to render cutting through or partly through mediate abutments 5, the outer sides of which the film of oil on the cylinder walls hard to are flush with the outer curved surface of'the attain, whereby the collection and drainage of ring, the same as are the outer ends of the sec- 70.

the oil through the ring is more perfectly obtions 3 previously described. tained. At the same time at the upper and The abutments 5 are located around the ring lower outer corner portions of the ring recesses substantially midway between the outer ends of for oil holding are produced thereby maintaining the sections 3 which are located between the a most effective seal between the ring and the ends of the slots 2. This provides narrow ribs 7 walls of the cylinder to prevent passage of ex- 6 separated from each other by the slots 2 which haust gases or of the compressed fuel charge under the tension of the compressed ring, as it'is from the combustion chamber'to the crank case in a cylinder, press into and cut through or parof the engine. tially through the film of oil with which a cyl- An understanding of the invention may be had inder is coated in engine operation, and thus 80 from the following description, taken in connecdirect the oil into the slots 2 for drainage to tion with the accompanying drawing, in which ring groove, from which it is carried through Fig. 1 is a plan view of a piston ring made in passages from the bottom of the ring groove to accordance with my invention. the interior of the piston, as is the usual prac- Fig. 2 is an edge view thereof. tice with oil collecting and conserving rings.

Fig. 3 is a fragmentary enlarged horizontal The location of the abutments 5 midway between section between the opposed flat sides of the ring. the integral sections 3 of the ring strengthens Fig. 4 is a fragmentary enlarged edge elevaeach section of the ring between any two parts tion of so much of the ring as is shown in Fig. 3, which without such abutments 5, would be 35 3, and considerably weakenedby the cutting of the slots 90 Figs. 5, 6 and 7 are cross sections on the planes 2; and the weakened portions of the ring would of lines 5-5, 6-6 and 77 of Fig. 4. be midway between said sections 3, and it is at Like reference characters refer to like parts in these midway points that the strengthening the different figures of the drawing. abutments 5 appear.

40 The ring 1 is made from the usual individual The parting 7 in the ring is made through 95 ring casting which is of uniform cross section one of the sections 3, as shown. leaving no weak and cast in a mold formedwith an out-of-round flanges at this point but providing a strong pattern. The casting may have a segment restructure at the parting. moved at one side such that when the ends of Moreover the ends of the abutments 5, as well the ring at such partings are brought together as the outer ends of the parts 3, in addition to 100 it will take a circular form, but when free to do the outer curved surfaces of the rib 6, bear so, will spring open at the parting made by the against the cylinder walls and together with the removing of such segment. Such ring casting bearing of theabutrnents 5 against the upper after machining at its outer curved side and at and lower sides of the ring grooves in which the its opposed flat sides provides what is known as ring is seated, serve to prevent fluttering or rock- 10L the ordinary snap ring. ing movementof the piston ring in operation.

In my invention a snap ring made as described Such fluttering or rocking movement is particuhas a plurality of drainage slots 2 out therelarly productive of blow-by, by which is meant through midway between the opposed fiat sides the passage of products of combustion or of the of the ring. The slots 2 are sawed from the compressed fuel charge past the piston from .the combustion chamber to the engine crank case.

The slots 2 having straight parallel walls, and being of full width from the outer to inner curved sides of the ring, when oil is scraped from the cylinder walls it passes directly through said slots to the ring grooves without restriction. This eliminates substantially any dangerof the slots clogging or filling up with carbon or' any deposit in the ring grooves, which is liable to occur when the slots carrying the oil are of less width than outer collecting ring grooves with which the slots are connected, present in many types of piston rings now manufactured.

The recesses at 4 are also useful in collecting and retaining oil which helps to perfectthe seal between the ring and the walls of the cylinder to thereby retain compression or exploded gases and prevent their passage or blowing by the piston. The construction of ring described is readily manufactured, simple and easy-to construct and at low cost, and with it the several advantages recited'are very satisfactorily attained. I

The invention is defined in the appended claims and is to be considered comprehensive of all forms of structure coming within their scope.

I claim:

1. A split piston ring having a plurality of circumferentially spaced slots extending radially therethrough at substantially the medial portion of said ring, said slots comprising substantially parallel side walls and inwardly converging end walls, said ring also having two series of circumferentially spaced arcuate grooves in its outer periphery, one series being formed in the upper outer corner of said ring and the other in the lower outer corner, the termini of said grooves forming pairs of circumferentially spaced aligned projections having portions flush with the outer peripheral surface of said ring, one pair of said aligned projections being formed at substantially the mid portion of each 

